Improvement in processes for treating wool



UNITED STATES PATENT OFFICEO' I THOMAS BARROVVS, OF DEDHAM, MASSACHUSETTS.

IMPROVEMENT lN PROCESSES FOR TREATING WOOL.

Specification forming part of Letters Patent- No. 13.206, dated July 10, 1855.

To all whom it may concern.-

Be it known that I, THOMAS BARROWS, of Dedham, in the county of Norfolk and State of Massachusetts, have made a new and useful invention or improvement whereby wool may be not only cleansed, softened, and prepared in an improved manner for perfecting the finish of wool goods, but enabled to take dyes uniformly and to great advantage; and 1 do hereby declare that the same is hereinafter fully described.

After wool has been cleansed in the usual way by washing in warm brine, or soap and water orweak alkaline solutions, there remains at the points where the iinbrications of the fibers are most close a certain portion of grease or yolk, combined with an earthy base, which neither of the agents above named will remove, and this substance, usually passing all the operations of manufacturing and dyeing, can be found in the.finished cloths, preventing the softnessof carefully-purified wool from beingobservable in them. The locks of the wool and portions of every fleece, from the adhesion of manure or other causes, present curled and yellow ends, called dead wool, which do not readily receive dyes-a fact which is more especially evident in dyeing with indigo. The most carefully-cleansed wool of an y fleece takes under the sameconditions of treatment various shades of color, some portions even remaining nearly white.

It has been the general impression among wool-manufacturers that the parts of the fleece which have thus become dead wool were oxidized and changed in a manner preventing them from being restored to their former condition or natural state. I find from experiments made on many varieties of wool, both.

foreign and domestic, that the property of deadness and general injury is due to a reductive or hydrogenating eflect, often the result of putrefactive fermentation, and that by proper oxidizing agents the natural condition can be restored.

Having thus premised, 1 will proceed to detail the steps of a method by which wool can be renderedmuch softer than usual and prepared to receive dyes quite uniformly throughout the fleece.

Two hundred pounds of sorted fleece-wool,

having been cleansed, will when dried weigh about onehundred and fifty pounds. In cases where the wool loses less weight in the scouring operation I have regard to this loss in proportioning the quantity of the oxidizing agent employed, using so much more of the latter as will make it equal for a given weight of clean, dry wool. The wet wool resulting from two hundred pounds of fleece-wool which has been secured by brine or soap, or in any ordinary manner, is to be passed after a careful rinsing into a bath prepared as follows: In a scouringtub of wood, fitted, as usual, for heating by steam and containing so much water as will cover the wool, I dissolve six pounds of saltpeter, nitrate of soda, chlorate of potash, or other oxidizing salt-such as nitrate of ammonia or an equivalent-which will cause the deoxidized wool to receive oxygen in the air, raising the temperature of the bath to 150 or 160 Fahrenheit. Into this bath the rinsed wool from two hundred pounds of fleece-wool is passed, and, with occasional moving by the pole, is allowed to repose thirty or forty minutes. It is next to be removed to the extractor, when the watcr is expelled, and afterward dried as usual. Successive parcels, each resulting from two hundred pounds of fleecewool, are thus to be passed through the oxidizing-bath, an addition of two pounds of the saltpeter or other oxidizing-salt being made before each parcel of wool is placed in it. Very bad wool, or that containing much dead wool, requires longer time in the bath, practice enabling any one to apportion time to quality. The effect of this bath of a hot solution of saltpeter is to produce a decomposition of the earthy soap existing in the closest interstices between the lapping of the scales or imbricaoxidizing-salts instead of saline compounds of another class-such as sal-ammoniac-whieh will partially remove the earthy soap. It is a specific oxidizing or changing effect on the -hurls, dead ends, or dead wool which 'is thus produced in the use of oxidizing-salts. The dead wool after treatment in the oxidizing-bath will take the dyes generally as well as the natural wool, and so well marked is this effect that I can produce it in the mordanting-bath, or even dye-bath, on wool which has not been treated in the oxidizing-bath; but prefer the use'of the latter in all cases. The

wool to be dyed need not be dried from the oxidizing-bath, it being sufficient to extract the water or allow the wool to drain over nigh t.

THO MAS BARROWS.

Witnesses:

R. H. EDDY, F. P. HALE, Jr. 

